Amphotericin B has been the standard of care for serious fungal infections, but treatment is often limited by its nephrotoxicity. The first study in the develoment of IV itraconazole was to assess the tolerability and safety and to describe the kinetics. No adverse experiences were reported by the four volunteers. IV itraconazole was then given followed by oral solution to patients in the intensive care unit and patients with hematologic malignancies. These studies revealed that patients receiving oral solution twice daily tended to have higher trough levels than those at the conclusion of IV dosing, but patients receiving only once daily oral dosing tended to have similar or somewhat lower trough levels. Itraconazole capsules are approved for the treatment of blastomycosis and histoplasmosis and can be used as first line therapy for patients with mild to moderate forms of these diseases. It is used as a consolidation therapy for patients with severe disease after a short course of IV amphotericin-B. For patients with more severe disease or those unable to take oral capsules, an IV form of itraconazole that provides reliable blood concentration levels in ill patients with fewer toxicities than amphotericin-B would be very beneficial. The primary purpose of the current study is to assess the safety of IV itraconazole compared to the standard of care (amphotericin-B). The study will also assess the clinical, microbiological, and overall response to therapy at the end of IV induction therapy and after PO consolidation therapy.